mono/metadata/gc-internals.h

   1 /**
   2  * \file
   3  * Internal GC interface
   4  *
   5  * Author: Paolo Molaro <lupus@ximian.com>
   6  *
   7  * (C) 2002 Ximian, Inc.
   8  * Copyright 2012 Xamarin Inc (http://www.xamarin.com)
   9  * Licensed under the MIT license. See LICENSE file in the project root for full license information.
  10  */
  11
  12 #ifndef __MONO_METADATA_GC_INTERNAL_H__
  13 #define __MONO_METADATA_GC_INTERNAL_H__
  14
  15 #include <glib.h>
  16 #include <mono/utils/gc_wrapper.h>
  17 #include <mono/metadata/object-internals.h>
  18 #include <mono/metadata/threads-types.h>
  19 #include <mono/sgen/gc-internal-agnostic.h>
  20 #include <mono/metadata/icalls.h>
  21
  22 #define mono_domain_finalizers_lock(domain) mono_os_mutex_lock (&(domain)->finalizable_objects_hash_lock);
  23 #define mono_domain_finalizers_unlock(domain) mono_os_mutex_unlock (&(domain)->finalizable_objects_hash_lock);
  24
  25 /* Register a memory area as a conservatively scanned GC root */
  26 #define MONO_GC_REGISTER_ROOT_PINNING(x,src,key,msg) mono_gc_register_root ((char*)&(x), sizeof(x), MONO_GC_DESCRIPTOR_NULL, (src), (key), (msg))
  27
  28 #define MONO_GC_UNREGISTER_ROOT(x) mono_gc_deregister_root ((char*)&(x))
  29
  30 /*
  31  * Return a GC descriptor for an array containing N pointers to memory allocated
  32  * by mono_gc_alloc_fixed ().
  33  */
  34 /* For SGEN, the result of alloc_fixed () is not GC tracked memory */
  35 #define MONO_GC_ROOT_DESCR_FOR_FIXED(n) (mono_gc_is_moving () ? mono_gc_make_root_descr_all_refs (0) : MONO_GC_DESCRIPTOR_NULL)
  36
  37 /* Register a memory location holding a single object reference as a GC root */
  38 #define MONO_GC_REGISTER_ROOT_SINGLE(x,src,key,msg) do { \
  39         g_assert (sizeof (x) == sizeof (MonoObject*)); \
  40         mono_gc_register_root ((char*)&(x), sizeof(MonoObject*), mono_gc_make_root_descr_all_refs (1), (src), (key),(msg)); \
  41         } while (0)
  42
  43 /*
  44  * This is used for fields which point to objects which are kept alive by other references
  45  * when using Boehm.
  46  */
  47 #define MONO_GC_REGISTER_ROOT_IF_MOVING(x,src,key,msg) do { \
  48         if (mono_gc_is_moving ()) \
  49                 MONO_GC_REGISTER_ROOT_SINGLE(x,src,key,msg);            \
  50 } while (0)
  51
  52 #define MONO_GC_UNREGISTER_ROOT_IF_MOVING(x) do { \
  53         if (mono_gc_is_moving ()) \
  54                 MONO_GC_UNREGISTER_ROOT (x);                    \
  55 } while (0)
  56
  57 /* useful until we keep track of gc-references in corlib etc. */
  58 #define IS_GC_REFERENCE(class,t) (mono_gc_is_moving () ? FALSE : ((t)->type == MONO_TYPE_U && (class)->image == mono_defaults.corlib))
  59
  60 void   mono_object_register_finalizer               (MonoObject  *obj);
  61
  62 void
  63 mono_object_register_finalizer_handle (MonoObjectHandle obj);
  64
  65 extern void mono_gc_init (void);
  66 extern void mono_gc_base_init (void);
  67 extern void mono_gc_cleanup (void);
  68 extern void mono_gc_base_cleanup (void);
  69 extern void mono_gc_init_icalls (void);
  70
  71 /*
  72  * Return whenever the current thread is registered with the GC (i.e. started
  73  * by the GC pthread wrappers on unix.
  74  */
  75 extern gboolean mono_gc_is_gc_thread (void);
  76
  77 extern gboolean mono_gc_is_finalizer_internal_thread (MonoInternalThread *thread);
  78
  79 extern void mono_gc_set_stack_end (void *stack_end);
  80
  81 /* only valid after the RECLAIM_START GC event and before RECLAIM_END
  82  * Not exported in public headers, but can be linked to (unsupported).
  83  */
  84 gboolean mono_object_is_alive (MonoObject* obj);
  85 gboolean mono_gc_is_finalizer_thread (MonoThread *thread);
  86
  87 void mono_gchandle_set_target (guint32 gchandle, MonoObject *obj);
  88
  89 /*Ephemeron functionality. Sgen only*/
  90 gboolean    mono_gc_ephemeron_array_add (MonoObject *obj);
  91
  92 /* User defined marking function */
  93 /* It should work like this:
  94  * foreach (ref in GC references in the are structure pointed to by ADDR)
  95  *    mark_func (ref)
  96  */
  97 typedef void (*MonoGCMarkFunc)     (MonoObject **addr, void *gc_data);
  98 typedef void (*MonoGCRootMarkFunc) (void *addr, MonoGCMarkFunc mark_func, void *gc_data);
  99
 100 /* Create a descriptor with a user defined marking function */
 101 MonoGCDescriptor mono_gc_make_root_descr_user (MonoGCRootMarkFunc marker);
 102
 103 /* Return whenever user defined marking functions are supported */
 104 gboolean mono_gc_user_markers_supported (void);
 105
 106 /* desc is the result from mono_gc_make_descr*. A NULL value means
 107  * all the words might contain GC pointers.
 108  * The memory is non-moving and it will be explicitly deallocated.
 109  * size bytes will be available from the returned address (ie, descr
 110  * must not be stored in the returned memory)
 111  */
 112 MonoObject* mono_gc_alloc_fixed      (size_t size, MonoGCDescriptor descr, MonoGCRootSource source, void *key, const char *msg);
 113
 114 // C++ callers outside of metadata (mini/tasklets.c) must use mono_gc_alloc_fixed_no_descriptor
 115 // instead of mono_gc_alloc_fixed, or else compile twice -- boehm and sgen.
 116 MonoObject*
 117 mono_gc_alloc_fixed_no_descriptor (size_t size, MonoGCRootSource source, void *key, const char *msg);
 118
 119 void  mono_gc_free_fixed             (void* addr);
 120
 121 /* make sure the gchandle was allocated for an object in domain */
 122 gboolean mono_gchandle_is_in_domain (guint32 gchandle, MonoDomain *domain);
 123 void     mono_gchandle_free_domain  (MonoDomain *domain);
 124
 125 typedef void (*FinalizerThreadCallback) (gpointer user_data);
 126
 127 MonoObject*
 128 mono_gc_alloc_pinned_obj (MonoVTable *vtable, size_t size);
 129
 130 MonoObjectHandle
 131 mono_gc_alloc_handle_pinned_obj (MonoVTable *vtable, gsize size);
 132
 133 MonoObject*
 134 mono_gc_alloc_obj (MonoVTable *vtable, size_t size);
 135
 136 MonoObjectHandle
 137 mono_gc_alloc_handle_obj (MonoVTable *vtable, gsize size);
 138
 139 MonoArray*
 140 mono_gc_alloc_vector (MonoVTable *vtable, size_t size, uintptr_t max_length);
 141
 142 MonoArrayHandle
 143 mono_gc_alloc_handle_vector (MonoVTable *vtable, gsize size, gsize max_length);
 144
 145 MonoArray*
 146 mono_gc_alloc_array (MonoVTable *vtable, size_t size, uintptr_t max_length, uintptr_t bounds_size);
 147
 148 MonoArrayHandle
 149 mono_gc_alloc_handle_array (MonoVTable *vtable, gsize size, gsize max_length, gsize bounds_size);
 150
 151 MonoString*
 152 mono_gc_alloc_string (MonoVTable *vtable, size_t size, gint32 len);
 153
 154 MonoStringHandle
 155 mono_gc_alloc_handle_string (MonoVTable *vtable, gsize size, gint32 len);
 156
 157 MonoObject*
 158 mono_gc_alloc_mature (MonoVTable *vtable, size_t size);
 159
 160 MonoGCDescriptor mono_gc_make_descr_for_string (gsize *bitmap, int numbits);
 161
 162 MonoObjectHandle
 163 mono_gc_alloc_handle_mature (MonoVTable *vtable, gsize size);
 164
 165 void mono_gc_register_obj_with_weak_fields (void *obj);
 166 void
 167 mono_gc_register_object_with_weak_fields (MonoObjectHandle obj);
 168
 169 typedef void (*MonoFinalizationProc)(gpointer, gpointer); // same as SGenFinalizationProc, GC_finalization_proc
 170
 171 void  mono_gc_register_for_finalization (MonoObject *obj, MonoFinalizationProc user_data);
 172 void  mono_gc_add_memory_pressure (gint64 value);
 173 MONO_API int   mono_gc_register_root (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, void *key, const char *msg);
 174 void  mono_gc_deregister_root (char* addr);
 175 void  mono_gc_finalize_domain (MonoDomain *domain);
 176 void  mono_gc_run_finalize (void *obj, void *data);
 177 void  mono_gc_clear_domain (MonoDomain * domain);
 178 /* Signal early termination of finalizer processing inside the gc */
 179 void  mono_gc_suspend_finalizers (void);
 180
 181
 182 /*
 183  * Register a root which can only be written using a write barrier.
 184  * Writes to the root must be done using a write barrier (MONO_ROOT_SETREF).
 185  * If the root uses an user defined mark routine, the writes are not required to be
 186  * to the area between START and START+SIZE.
 187  * The write barrier allows the GC to avoid scanning this root at each collection, so it
 188  * is more efficient.
 189  * FIXME: Add an API for clearing remset entries if a root with a user defined
 190  * mark routine is deleted.
 191  */
 192 int mono_gc_register_root_wbarrier (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, void *key, const char *msg);
 193
 194 void mono_gc_wbarrier_set_root (gpointer ptr, MonoObject *value);
 195
 196 /* Set a field of a root registered using mono_gc_register_root_wbarrier () */
 197 #define MONO_ROOT_SETREF(s,fieldname,value) do {        \
 198         mono_gc_wbarrier_set_root (&((s)->fieldname), (MonoObject*)value); \
 199 } while (0)
 200
 201 /* fast allocation support */
 202
 203 typedef enum {
 204         // Regular fast path allocator.
 205         MANAGED_ALLOCATOR_REGULAR,
 206         // Managed allocator that just calls into the runtime.
 207         MANAGED_ALLOCATOR_SLOW_PATH,
 208         // Managed allocator that works like the regular one but also calls into the profiler.
 209         MANAGED_ALLOCATOR_PROFILER,
 210 } ManagedAllocatorVariant;
 211
 212 int mono_gc_get_aligned_size_for_allocator (int size);
 213 MonoMethod* mono_gc_get_managed_allocator (MonoClass *klass, gboolean for_box, gboolean known_instance_size);
 214 MonoMethod* mono_gc_get_managed_array_allocator (MonoClass *klass);
 215 MonoMethod *mono_gc_get_managed_allocator_by_type (int atype, ManagedAllocatorVariant variant);
 216
 217 guint32 mono_gc_get_managed_allocator_types (void);
 218
 219 /* Return a short string identifying the GC, indented to be saved in AOT images */
 220 const char *mono_gc_get_gc_name (void);
 221
 222 /* Fast write barriers */
 223 MonoMethod* mono_gc_get_specific_write_barrier (gboolean is_concurrent);
 224 MonoMethod* mono_gc_get_write_barrier (void);
 225
 226 /* Fast valuetype copy */
 227 /* WARNING: [dest, dest + size] must be within the bounds of a single type, otherwise the GC will lose remset entries */
 228 G_EXTERN_C void mono_gc_wbarrier_range_copy (gpointer dest, gconstpointer src, int size);
 229
 230 typedef void (*MonoRangeCopyFunction)(gpointer, gconstpointer, int size);
 231
 232 MonoRangeCopyFunction
 233 mono_gc_get_range_copy_func (void);
 234
 235 /*
 236  * Functions supplied by the runtime and called by the GC. Currently only used
 237  * by SGEN.
 238  */
 239 typedef struct {
 240         /*
 241          * Function called during thread startup/attach to allocate thread-local data
 242          * needed by the other functions.
 243          */
 244         gpointer (*thread_attach_func) (void);
 245         /*
 246          * Function called during thread deatch to free the data allocated by
 247          * thread_attach_func.
 248          */
 249         void (*thread_detach_func) (gpointer user_data);
 250         /*
 251          * Function called from every thread when suspending for GC. It can save
 252          * data needed for marking from thread stacks. user_data is the data returned
 253          * by attach_func. This might called with GC locks held and the word stopped,
 254          * so it shouldn't do any synchronization etc.
 255          */
 256         void (*thread_suspend_func) (gpointer user_data, void *sigcontext, MonoContext *ctx);
 257         /*
 258          * Function called to mark from thread stacks. user_data is the data returned
 259          * by attach_func. This is called twice, with the word stopped:
 260          * - in the first pass, it should mark areas of the stack using
 261          *   conservative marking by calling mono_gc_conservatively_scan_area ().
 262          * - in the second pass, it should mark the remaining areas of the stack
 263          *   using precise marking by calling mono_gc_scan_object ().
 264          */
 265         void (*thread_mark_func) (gpointer user_data, guint8 *stack_start, guint8 *stack_end, gboolean precise, void *gc_data);
 266         /*
 267          * Function called for debugging to get the current managed method for
 268          * tracking the provenances of objects.
 269          */
 270         gpointer (*get_provenance_func) (void);
 271 } MonoGCCallbacks;
 272
 273 /* Set the callback functions callable by the GC */
 274 void mono_gc_set_gc_callbacks (MonoGCCallbacks *callbacks);
 275 MonoGCCallbacks *mono_gc_get_gc_callbacks (void);
 276
 277 /* Functions callable from the thread mark func */
 278
 279 /* Scan the memory area between START and END conservatively */
 280 void mono_gc_conservatively_scan_area (void *start, void *end);
 281
 282 /* Scan OBJ, returning its new address */
 283 void *mono_gc_scan_object (void *obj, void *gc_data);
 284
 285 /* Return the suspend signal number used by the GC to suspend threads,
 286    or -1 if not applicable. */
 287 int mono_gc_get_suspend_signal (void);
 288
 289 /* Return the suspend signal number used by the GC to suspend threads,
 290    or -1 if not applicable. */
 291 int mono_gc_get_restart_signal (void);
 292
 293 /*
 294  * Return a human readable description of the GC in malloc-ed memory.
 295  */
 296 char* mono_gc_get_description (void);
 297
 298 /*
 299  * Configure the GC to desktop mode
 300  */
 301 void mono_gc_set_desktop_mode (void);
 302
 303 /*
 304  * Return whenever this GC can move objects
 305  */
 306 gboolean mono_gc_is_moving (void);
 307
 308 typedef void* (*MonoGCLockedCallbackFunc) (void *data);
 309
 310 void* mono_gc_invoke_with_gc_lock (MonoGCLockedCallbackFunc func, void *data);
 311
 312 int mono_gc_get_los_limit (void);
 313
 314 guint64 mono_gc_get_allocated_bytes_for_current_thread (void);
 315
 316 guint8* mono_gc_get_card_table (int *shift_bits, gpointer *card_mask);
 317 guint8* mono_gc_get_target_card_table (int *shift_bits, target_mgreg_t *card_mask);
 318 gboolean mono_gc_card_table_nursery_check (void);
 319
 320 void* mono_gc_get_nursery (int *shift_bits, size_t *size);
 321
 322 // Don't use directly; set/unset MONO_THREAD_INFO_FLAGS_NO_GC instead.
 323 void mono_gc_skip_thread_changing (gboolean skip);
 324 void mono_gc_skip_thread_changed (gboolean skip);
 325
 326 #ifndef HOST_WIN32
 327 int mono_gc_pthread_create (pthread_t *new_thread, const pthread_attr_t *attr, void *(*start_routine)(void *), void *arg);
 328 #endif
 329
 330 /*
 331  * Return whenever GC is disabled
 332  */
 333 gboolean mono_gc_is_disabled (void);
 334
 335 /*
 336  * Return whenever this is the null GC
 337  */
 338 gboolean mono_gc_is_null (void);
 339
 340 void mono_gc_set_string_length (MonoString *str, gint32 new_length);
 341
 342 #if defined(__MACH__)
 343 void mono_gc_register_mach_exception_thread (pthread_t thread);
 344 pthread_t mono_gc_get_mach_exception_thread (void);
 345 #endif
 346
 347 gboolean mono_gc_precise_stack_mark_enabled (void);
 348
 349 typedef struct _RefQueueEntry RefQueueEntry;
 350
 351 struct _RefQueueEntry {
 352         void *dis_link;
 353         guint32 gchandle;
 354         MonoDomain *domain;
 355         void *user_data;
 356         RefQueueEntry *next;
 357 };
 358
 359 struct _MonoReferenceQueue {
 360         RefQueueEntry *queue;
 361         mono_reference_queue_callback callback;
 362         MonoReferenceQueue *next;
 363         gboolean should_be_deleted;
 364 };
 365
 366 enum {
 367         MONO_GC_FINALIZER_EXTENSION_VERSION = 1,
 368 };
 369
 370 typedef struct {
 371         int version;
 372         gboolean (*is_class_finalization_aware) (MonoClass *klass);
 373         void (*object_queued_for_finalization) (MonoObject *object);
 374 } MonoGCFinalizerCallbacks;
 375
 376 MONO_API void mono_gc_register_finalizer_callbacks (MonoGCFinalizerCallbacks *callbacks);
 377
 378
 379 #ifdef HOST_WIN32
 380 BOOL APIENTRY mono_gc_dllmain (HMODULE module_handle, DWORD reason, LPVOID reserved);
 381 #endif
 382
 383 MonoVTable *mono_gc_get_vtable (MonoObject *obj);
 384
 385 guint mono_gc_get_vtable_bits (MonoClass *klass);
 386
 387 void mono_gc_register_altstack (gpointer stack, gint32 stack_size, gpointer altstack, gint32 altstack_size);
 388
 389 gboolean mono_gc_is_critical_method (MonoMethod *method);
 390
 391 G_EXTERN_C // due to THREAD_INFO_TYPE varying
 392 gpointer mono_gc_thread_attach (THREAD_INFO_TYPE *info);
 393
 394 G_EXTERN_C // due to THREAD_INFO_TYPE varying
 395 void mono_gc_thread_detach_with_lock (THREAD_INFO_TYPE *info);
 396
 397 G_EXTERN_C // due to THREAD_INFO_TYPE varying
 398 gboolean mono_gc_thread_in_critical_region (THREAD_INFO_TYPE *info);
 399
 400 /* If set, print debugging messages around finalizers. */
 401 extern gboolean mono_log_finalizers;
 402
 403 /* If set, do not run finalizers. */
 404 extern gboolean mono_do_not_finalize;
 405 /* List of names of classes not to finalize. */
 406 extern gchar **mono_do_not_finalize_class_names;
 407
 408 #endif /* __MONO_METADATA_GC_INTERNAL_H__ */